We treated destructive behavior maintained by both social-positive (i.e., access to tangibles) and social-negative (i.e., escape from demands) reinforcement in an individual diagnosed with autism ...spectrum disorder using functional communication training (FCT). We then thinned the schedule of reinforcement for the tangible function using a multiple schedule (mult FCT) and later thinned the availability of escape using a chained schedule (chain FCT). Both treatments proved effective at maintaining functional communicative responses while decreasing destructive behavior to near-zero levels. In addition, treatment effects maintained when we rapidly thinned mult FCT to the terminal schedule. Throughout chain-FCT schedule thinning, we assessed client preference for each schedule-thinning arrangement (mult FCT or chain FCT) using a concurrent-chains procedure. Client preference reliably shifted from chain FCT to mult FCT as the response requirement increased and the proportion of session spent in reinforcement began to favor mult FCT. We discuss the clinical implications of these findings.
With its generally recognized benefits of clean and safe working environment and good quality, prefabricated house construction (PHC) as a solution is gaining momentum in the face of various housing ...challenges in Hong Kong's construction industry. Although prefabrication has its own benefits, its fundamental disadvantages of fragmentation, discontinuity, poor interoperability, and scarce real-time information availability have imposed significant adverse influence on the schedule performance of prefabricated house construction. As a result, despite the promise of the government to provide sufficient houses and harmonious housing, schedule delay problems still frequently beset the industry of PHC. To help address schedule delay problems encountered in the construction of prefabrication housing, this research first identified and analysed critical schedule risk factors that may have significant influence on the schedule performance of PHC. Based on the identified schedule risks, the challenges and corresponding required functions for enhancing schedule performance are determined. Then, a radio frequency identification device (RFID)-enabled BIM platform that integrates various involved stakeholders, information/data flow, offshore prefabrication procedures, and state-of-the-art construction technologies, is developed to handle the critical schedule factors. Smart construction objects and RFID-enabled smart gateway work collaboratively to ease operations within the three echelons of prefabrication manufacturing, logistics and on-site assembly construction, while real-time captured data are used to form a closed-loop visibility and traceability mode in which different end users can supervise the construction statuses, progresses in real time. The developed platform can provide various services, tools and mechanisms to different stakeholders, improve the success of daily operations and decision makings throughout PHC management, such that critical schedule risks can be mitigated and the schedule performance of PHC can be enhanced to ensure timely project delivery.
barker l.m. & nussbaum m.a. (2011) Fatigue, performance and the work environment: a survey of registered nurses. Journal of Advanced Nursing67(6), 1370–1382.
Aims. This paper is a report of a study ...of perceived levels of mental, physical and total fatigue, and also acute and chronic fatigue states, among registered nurses. Relationships between dimensions of fatigue and performance were investigated, as were differences in fatigue across levels of several demographic and work environment variables.
Background. Fatigue is a factor that has been linked to performance decrements in healthcare workers. As a result of the nature of their work, nurses may be particularly susceptible to multiple dimensions of fatigue, and their performance is closely linked to patient safety.
Methods. An online survey was used to measure mental, physical, and total fatigue dimensions, acute and chronic fatigue states, and performance. Participants were recruited via convenience sampling in cooperation with professional nursing organizations; 745 registered nurses completed the survey between February 2008 and April 2009.
Results. Reported mental fatigue levels were higher than physical fatigue levels, and acute fatigue levels were higher than chronic fatigue levels. All fatigue dimensions and states were negatively correlated with perceived performance. Longer shift lengths and hours worked per week were associated with increases in physical and total fatigue levels. Mental, physical and total fatigue levels also differed with shift schedule.
Conclusions. Fatigue levels were negatively correlated with performance, further supporting the role of fatigue in nurse performance. Work environment variables were strongly associated with differences in perceived levels of fatigue. By altering the work environment, it may thus be possible to reduce fatigue levels and the rates of medical errors.
Rationale
Schedule-induced drinking (SID) reproduces an excessive and repetitive behavioural pattern that has led to propose this procedure as an animal model to study compulsive behaviours. Although ...it is known that cannabis can cause several adverse effects, in recent years there has been great interest in the medical application of cannabis derivatives for obsessive-compulsive related disorders.
Objectives
The present study investigated the effects of repeated THC administration on rates of previously acquired SID, as well as the possible alteration of its temporal distribution along inter-food intervals.
Methods
Male Wistar rats acquired SID under a 30 min fixed-time 30-sec food delivery schedule (from 30 to 43 sessions to reach a stable level). Thereafter, 5 or 10 mg/kg daily i.p. injections of THC or vehicle were repeatedly administered for 7 days to evaluate the effects on SID.
Results
Repeated THC administration at a dose of 5 mg/kg resulted in an increase on licking. Surprisingly, no effects on SID were observed with the 10 mg/kg dose. However, magazine entries were reduced with both THC doses. THC also modified the temporal distributions of licking and magazine entries during inter-food intervals.
Conclusions
The present results show that repeated THC administration may (i) increase induced licking at moderate doses, (ii) reduce magazine entries, and (iii) affect the temporal pattern of SID. These findings suggest that THC does not appear to be beneficial to reduce compulsive behaviour in this animal model, while another collateral effect of THC —such as a greater habitual-like behaviour— needs to be considered.
The study assessed the effects of whole- or half-night shifts on leptin, melatonin, sex hormones, interleukin (IL)-1β, tumor necrosis factor-α (TNF-α), IL-6, hematological parameters, sleep quality ...and attentional performance in women working in the health sector.
Women working whole-night shifts (16:00-08:00 hours, n = 20), half-night shifts (16:00-24:00 hours, n = 20) or day shifts (08:00-16:00 hours, n = 20) participated in the study. Blood pressure, respiratory rate, proximal skin temperature (forehead), blood glucose, leptin, melatonin, estradiol, progesterone, IL-1β, TNF-α, and IL-6 concentrations, complete blood count and erythrocyte sedimentation rate (ESR) were measured in the beginning and at the end of the shifts. The participants filled in sleep quality questionnaires and performed visual attention tests.
Half- and whole-night shifts caused problems in sleep duration and quality and disturbed the melatonin rhythm. Women working both half- and whole-night shifts had significantly higher nucleated erythrocytes (P = 0.006), eosinophils (P = 0.031), lymphocytes (P = 0.001) and leptin concentrations (P = 0.001) but had lower ESR (P = 0.046) and neutrophil percentage (P = 0.001) than that of day-time workers. Whole-night shifts caused additional changes including lower attentional performance (P = 0.035), lower platelet counts (P = 0.000) and lower estradiol levels (P = 0.029), but higher TNF-α levels (P = 0.000), than the control group. Moreover, whole-night shifts increased IL-1β levels before the shift (P < 0.001) and increased IL-6 levels over the half-night shifts (P < 0.05).
Half-night shifts disturbed sleep parameters and the melatonin rhythm, perturbed blood cell turnover and increased leptin levels. Whole-night shifts caused additional problems including suppressed estradiol, activated inflammatory responses and decreased visual attention. All together, the data suggest that night shifts, especially whole-night shifts, should be refrained from or countermeasures should be taken.
Three experiments examined the effect of instructions on human free-operant performance on random ratio (RR) and random interval (RI) schedules. Both rates of responding, and the microstructure of ...behavior, were explored to determine whether bout-initiation and within-bout responding may be controlled by different processes. The results demonstrated that responding in acquisition (Experiments 1 and 2) and extinction (Experiment 3) was impacted in line with given instructions. During acquisition, rates were higher on RR compared to RI for accurate and minimal instructions. During extinction, rates decreased when there were minimal instructions. However, instructions had a greater impact on within-bout responding, than they did on bout-initiation responding. Overall rates of responding, and within-bout rates, varied in line with the nature of the instructions, but bout-initiation responding did not (Experiments 1 and 2). Resistance to extinction was increased by instructions in terms of overall responding and within-bout rates, but not in terms of bout-initiation rates (Experiment 3). These data are consistent with the hypothesis that bout-initiation responding may be less impacted by instructions than within-bout responding, speculatively, the former is stimulus-driven, automatic/habitual, and less accessible to conscious processing.
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CEKLJ, FFLJ, NUK, ODKLJ, PEFLJ
This paper investigates the extent of delays in large government investment projects in Norway. We use a data set consisting of 112 road, railway, building, defence and ICT projects. All projects ...have been planned and implemented within a standardised governance framework. This ensures a more robust assessment of causation compared to studies that use data from disparate projects around the world. The results have shown that about half of the projects are completed on or before time, there are a large proportion of projects that are severely delayed. Defence projects are particularly prone to problems during their delivery. This is in accordance with findings from other countries. The paper shows that there has been a slight improvement in time, that is, the extent of delays seems to have been reduced over the last 20 years. Counter to expectations, projects that are delayed do not seem to be more at risk to overrun their costs.
The new juncture of concerns about climate change and finite energy resources has been changing products and processes toward a path of preserving the environment and energy efficiency. Electric ...mobility along with sustainable charging stations constitutes one way to reduce environmental impacts. However, the coordination of energy resources triggers several challenges that require proper energy management strategies. This work proposes an optimization model to minimize the operational costs of a sustainable charging station (CS) under different charging types for an electric bus, as part of an electric mobility living lab in the public transport system of the University of Campinas (Unicamp, Brazil). The problem is solved using a dynamic approach based on a rolling horizon method that uses as input real data obtained from installed photovoltaic panels and from the operation of an electric bus circulating at Unicamp facilities. The results show that the charging schedule defined by the optimization model is cost effective, reducing the monthly cost by 52% when compared with the actual charging schedule carried out on campus. Furthermore, the inclusion of photovoltaic panels results in a significant reduction in operational costs, which can be enhanced by the inclusion of a battery energy storage system. The results also demonstrate that the operational costs of the CS are not only linked to technical issues, but also to regulatory issues. Then, the proposed optimization model is a flexible tool that allows for the analysis of different charging schedules and the operation of a fleet of electric buses via sustainable charging stations.
•An optimization model for the operation of sustainable charging stations in a university campus.•A dynamic charging schedule of a fleet of E-buses within different charging types.•Uncertainties of photovoltaic generation and arrival time of E-Buses are considered.•Results are obtained using real data from a living lab at a university campus.•The proposed model provides cost optimal solutions and can be used for different studies.
The behavioral processes determining the magnitude of the resurgence of destructive behavior during reinforcement schedule thinning have yet to be described, despite an uptick in prevalence research ...on the topic. As predicted by Resurgence as Choice theory, recent animal research has found that resurgence increases with the magnitude of a downshift in alternative reinforcement. Here we reanalyze the data from 2 recent prevalence studies to determine whether the size of the decrease in alternative reinforcement availability predicts the magnitude of resurgence in the clinic. Results from this retrospective analysis suggest that resurgence of destructive behavior increases significantly with decreases in the availability of alternative reinforcement. Implications for future research and translations of theoretical analyses to the clinic are discussed.
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